Rudy Giuliani

Stood toe-to-toe with Mitt Romney on fights over taxes and spending in the debate's hottest moment, and seemed to get the best of the exchange. Pounded the tax cutting theme. Went after Hillary Clinton (again). Talked about the Yankees (again). Closed strong (again). As we always say, every single day he survives on top, he grows stronger and gets closer to the nomination.

—By Mark Halperin